The invention relates to a relay for the operation of a belt tightener for automobile safety belts in event of a collision with an obstacle.
A relay arrangement in this field is known, which provides a known conduit or dry-reed contact arrangement for the switching initiated by an automobile collision, in which a permanent magnet, formed as a ring, is retained by springs. In the case of a collision with an obstacle, this permanent magnet is accelerated forwards along the longitudinal axis of the contact spring arrangement, against the spring pressure and this initiates the switching sequence for operation of the belt-tightener.
Such a relay must therefore be installed in an automobile in such a way that the conduit or dry-reed contact arrangement is aligned longitudinally with the longitudinal axis of the vehicle to be able to directly bring about the switching sequence in the event of a collision.
A disadvantage of this layout is that in the event of a stop initiated by a rear end collision from another automobile, a relay so installed does not operate due to the inertia of the annular magnet.
In order to be able to detect a collision shock from another automobile approaching from the rear and to initiate the corresponding switching sequence, an inversely spring-loaded second relay of this type would therefore have to be provided. Two such relays can therefore initiate a switching sequence in the event of both a frontal or rear-end collision when these shocks occur either in or close to the direction of the longitudinal axis of the vehicle.